German Patent Application No. DE 197 24 320 describes a method for producing an heatable antenna lens. A heatable antenna lens is described that is made of a dielectric substance, which has inside of it an array of electrical conductors, the electrically conductive array not lying in a plane.
On page 263 ff, design and operation of headlight cleaning systems are described from the book, “Automobile Electrical Systems, Automobile Electronic Systems”, Vieweg-Verlag, 3rd edition, 1998. Such headlight cleaning systems have the objective of removing the dirt on the lenses of the main headlights. The embodiment variant of the high-pressure washing systems described stands out in that it may be used both for glass lenses and for plastic lenses. The cleaning effect is determined mainly by the cleaning impulse of the water drops. As the important variables of the cleaning impulses, the distance between nozzle and lens, the size, the angle of incidence and the speed of incidence of the water drops, as well as the quantity of the water are named.